t/f synthetases are enzymes that combine two molecules together to make a bigger molecule
true
t/f increasing the substrate concentration of an enzyme catalyzed reaction will produce a linear increase in the reaction rate
false
t/f proteins that have useful biological functions represent a tiny, tiny fractino of possible proteins
true
t/f it is not possible to oxidize a molecule without increasing the oxygen content of the molecule
false
t/f "biochemical" high energy bonds are those bonds that have a relatively large difference in energy between the oxidized and reduced states
false
t/f in the enzyme complex alpha keto glutarate dehydrogenase, lipoic acid is present as a prosthetic group
true
t/f enzymes can catalyze reactions that are otherwise impossible
false
t/f noncompetitive enzyme inhibitors increase the Vmax
false
t/f prions have high percentages of beta helical structure
true
t/f all enzymes are proteins
false
t/f the reactions of pyruvate dehydrogenase occur in the endoplasmic reticulum
false
t/f when proteins fold they have less energy content when unfolded
true
t/f enzymes increase the rates of chemical reactions they catalyze by decreasing the energy difference between the reactants and products
false
t/f because they do not have mitochondria, mammalian red blood cells do not have the ability to perform anaerobic glycolysis
false
t/f all enzymatic reactions involving the formation or utilization of "biochemical high energy bonds" are physiologically irreversible
false
t/f some proteins cannot undergo reversible denaturation
true
t/f a manufacturer of a multi-B-vitamin dietary supplement correctly cliams that their product helps to "unlock the energy in the foods we eat"
true
t/f physiologically irreversible metabolic reactions may be defined as those for which there is no enzyme to catalyze the reverse reaction
true
t/f the specific activityof an enzyme is a description of the reactants accepted and the products produced by that enzyme
false
t/f in general noncompetitive enzyme inhibitors will not structurally resemble the substrate
true
t/f coenzyme A is often involved in phosphate group transfer reactions
false
t/f oxidation of a molecule, in general, increases teh energy content of hte molecule
false
t/f most biological oxidation reactions involve only single electron transfers
false
t/f succinyl coA contains "biochemical" high energy bonds
true
t/f enzyme catalyzed reactions that have a small deltaG are physiologically reversible
true
t/f conversion of glucose to 2 pyruvate through the reactions of glycolysis is physiologically irreversible
true
t/f cellulose in wood is a polymer of glucose
true
t/f peptide bonds vehave as if they were double bonds
true
t/f some redox cofactors can dissociate from their enzymes and catalyze single electron transfer reactions when they accumulate in their reduced forms
true
t/f acid diesters are generally unstable and release energy when they are hydrolyzed
true
t/f enzymes do not obey the laws of chemistry and physics
false
the first molecule derived from the carbons of glucose in the process of glycolysis that contains a biochemical high energy bond is _______
1,3-biophosphate-D-gluterate ???? hard to read
3 structural features of a polypeptide that might de-stabilize an alpha helix are
addition of a Dic sterme ??? hard to read, addition of the proline, and hydrophobic R groups in lipids
Vmax can be used as a measure of ______ while Km can be used as a measure of _______
affinity for an enzyme and substrate for one another?? hard to read
50% Es and 50% EI ??
two beneficial outcomes related to the ability of cells in your body to undergo anaerobic glycolysis are___
4 B vitamins required in their cofactor forms for conversion of pyruvate to acetyl CoA __
FAD, NAD, COA, TPP
3 ways that enzyme activities may be regulated by covalent alterations are
phosphorilation, dephosphorilation, and ???
3 possible ways to cause protiein denatureation are
raise temperature, mechanically strengthen, and lower pH
substances that are capable of disrupting non-covalent bonding interactions in proteins are called
chatotrophe substances??
starting at 4 degrees celcius, two effects that raising the temperature will have on an enzyme catalyzed reaction are
increases reaction rate and decreases the energy of activation
Give 2 redox reactions in which energy released from oxidizing the metabolite gets captured directly in the product molecule by the formation of a "biochemical high energy bond"
two substances formed in muscle cells as the result of anaerobic glycolysis that contribute to muscle soreness are
lactic acid and free radicals
two isomerization reactions from glycolysis that result in the same kind of changes in the substrates and products of the reactions are
DHAP --> glyceraldehyde-3-phosphate
glucose-g-phosphate --> ???-phosphate
define the term "vitamin" as it is commonly used
vitamins are nutritional substances for the lock there of the body
t/f endothermic reactions are those that result in the release of excess energy as heat
false
t/f proteins with complex energy diagrams cannot be denatured
false
t/f in order to oxidize a molecule it is necessary to incorporate oxygen atoms into it
false
t/f in general, when the substrate has a chiral center, the enzyme will accept only one of a pair of optical isomers as its substrate
true
t/f double stranded DNA and RNA absorb light at a wavelength of 269 nm more stronglythan single stranded DNA and RNA
false
t/f insulin can regulate gene expression in cells
true
t/f the purpose of both DNAand protein folding is compaction
false
t/f enzymes get more active as the pH increases
false
t/f specificity is a measure of an enzyme's ability to catalyze a reation with a molecule
false
t/f UV radiation will cause thymine dimer formation and single strand breaks in DNA
true
t/f reaction rates always contain a concentration term
true
t/f intra-strand base pairing in RNA loops can only be A-U or G-C
false
t/f teh 64 codons of mRNA encode 64 different amino acids
false
t/f enzymes supply the necessary energy of activation for the reactions they catalyze
false
t/f the overall process of glycolysis is physiologically irreversible
true
t/f kinase reactions are always physiologically irreversible
false
t/f one of the similarities between eukaryotic and prokaryotic chromosomal DNAs is that they both take the form of a negative supercoil
true
t/f those physiological reactions that are physiologically irreversible do not need to be regulated
false
t/f ribozymes catalyze chemical reactions involving nucleic acids
true
t/f it is not possible for proteins to be infective agents
false
t/f most polypeptide sequences are not capable of folding into structures that are biologically useful
true
t/f affinity is measure of an enzyme's ability to catalyze a reaction with a molecule
false
t/f NADH contains less energy than NAD+
false
t/f enzymes will have a temperature at which they are maximally active
true
t/f pyruvate is more oxidized than glucose
true
t/f many drugs exert their therapeutic action by inhibiting certain enzymes
true
t/f denaturation alters the primary structure of roteins
false
t/f the order of addition of inhibitor and substrate to an ESI complex in a simple non-competitive inhibitor situatin is generally not important
true
what reapir mechanismis used to correct de-aminated bases in DNA?
please suggest 3 possible reasons why protein cannot be directly translated (synthesized) from info encoded in DNA
Protenis too large to leave nucleus, DNA is stored in the nucleus and robosomes generally make proteins- locational barrier,
there needs to be a mechanism of correction found in having RNA- defense,.... -1 ??
and finally DNA= master copy so need mechanism to remove immuno-alternative splicing
3 possible ways to denature proteins are
increase temperature, change pH, and add chanthropie ??
4 different enzyme activities that participate in DNA replication are
helicases, RNA polymerases, ligases, and topisomerases??
in order to convert kinetic values (V max) for an enzyme to enzyme concentrations you need a value called the
Km value- affinity of ESI formation
the affinity constant for an inhibitor interaction with an enzyme is
Ki
3 bases found in DNA that are subject to de-amination reactions are
adenine, guanine, and cytosine
2 different ways to regulate enzyme activities by covalently modifying the enzyme molecule are
1,3-bisphosphao-D-glycerate?? and phosphorenol pyruvate??
two catalytic feats that enzymes do very well that other catylists don't necessarily do well are
target specific substrates and products
undercontrol of mechanisms to regulate efficiency in cell
________ is the oxidizing agent of glycoysis
?
all of the following are true about the A form of the DNA double helix except:
B. decreased number of base pairs per turn relative to the B form
hyperglycemia
a. is a condition where the blood is low in free fatty acids
b. causes water to accumulate in tissues
c. is the direct result of overheating
d. inhibits glucose transporters throughout the body
e. can cause capillary blood vessel walls to thicken at the expense of the vessle lumen
